Blasting cartridge and method and means for operating the same



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' BLASTING CARTRIDGE AND METHQD AND MEANS FOR OPERATING THEQSAME m. NMNWMY M N mm Patented May 3, 1932 pairs stares LAWRENCE E. LAWSON, OF CHICAGO, ILLINOIS, ASSIGNOR TO SAFETY COM PANY, OF CHICAGO,- ILLINOIS, A CORPORATION BLASTING CARTRIDGE AND METHOE ANT) MEANS FOR OPERATING THE SAME I Application filed October 7, 1929. Serial No. 3983374;

The present invention is concerned with a blasting cartridge and a method and means for operating the same. However, the invention is concerned more particularly with an operating method and means which may bea adapted to use with any known form of blasting device.

An object of the invention is to provide an entirely safe method and means for effecting the discharge of blasting devices.

A further object is to provide a remote control actuating device for blasting devices without the use of electricity.

A still further object is .to provide a positive actuation for blasting devices, with adequate protection against accidental discharge Specifically, it is an object of the invention to provide a fluid actuated means for effooting the discharge of blasting devices.

Another of the more specific objects of the invention is to provide'a fluid actuated means for effecting the discharge of gas charged blasting cartridges of the general type hereinafter described.

The principles of the invention are illustrated in the accompanying drawings, but it should be understood that they may be incor-- porated in a variety of structures diflering from that herein shown.

In the drawings,

Figure 1 is a view in longitudinal section of a portion of a blasting cartridge embodying my invention,

Figure 2is a transverse section along line 2 2-2 of Figure 1, 7

Figure 3 is an enlarged detail view in section, showing the charging valve,

Figure 4 IS a sectional view taken along line 4-4 of Figure'l, and

Figure 5 is a detail view of the bayonet slot connection between the heater and heater support. -The cartridge with which the present invention is illustrated is of that .type wherein a charge of compressed gas is employed as the blasting medium. structurally the cartridge consists of a metallic container 1 in which is formed a gas chamber 2. An end of the gas chamber is open but is adapted to be closedby means of a rupturabledisc fixed in position by a discharge cap. The particular form of the discharge mechanism is not herein shown since it forms no part of the present invention.

Leading into the gas chamber 2 is a charging passage 3 which communicates with a transversely arranged pocket 4 formed in the end of the body 1. This pocket is provided with screw threads for the reception-of a correspondingly threaded plug 6. A suitable packing gland 7 is secured to the plug and has engagement with the wall of the pocket in order to seal against the escape of gas from the chamber 4. A valve stem 8 is threaded centrally through the plug 6 and is provided on its end with a substantially conical valve 9 which is designed to cooperate with the passage 3 for the purpose of'controlling c0mmunication between chamber 4 and gas chamber 2. An angularly directed passage 10 extends froin the surface of the shell body inwardly to the chamber 4. At its outer extremity this passage 10 is enlarged to form a seat 11 adapted to receive a charging nozzle.

The end of the cartridge body is provided with screw threads for cooperation with similar threads formed internally of a cap member 12'. This cap member is of hollow construction and is elongated in an axial direc-' tion to provide acylinder 13 with which a passage 14 in the end of the cap communicates. Located within the cylinder 13 isa piston 15 secured to one end of a piston rod 16. r

The end of the cartridge body is provided with axial bore 17 through which the piston rod 16 is adapted to slide. A suitable .stuifing box 18 is provided to prevent the escape -of gas from the chamber 2 around the piston JOSE, the piston rod is provided with a transrerse opening 19 through which extends a Erangible pin 20. This pin is adapted to bev nserted'through an aperture 21 in one wall )f the cap and to have its opposite end seated n apocket 22 located at a diametrically opposite point in the cap wall. A pivoted cover plate 23 serves to secure the-pin in position. The end ofthe cartridge body 1 is re-- cessed as indicated at 24 to provide a pocket into which the sheared portion of the pin 20 may pass when the piston and piston rod are moved axially. The outer edge of this-pocket serves as an anvil or shear ring against which the pin may be forced by the pressure of the cgmpressed fluid in order to shear the pin at two definite points.

Within the gas chamber 2 there is provided a heater support 25 which is screw threaded in the end of .thecartridge as indicated at 26. A tubular heater unit 27 may be positioned the. support 25 and may be secured against axial'movement' with respect thereto by means of-a pin 28 carried by the heater and bayonet slots '29 formed in the support. The end of the heater may be pro vided'with a suitable form'of detonating cap;

with which the end 30 of the pistonrod l6 is adapted to cooperate to energize the heater.

- In view' of the foregoing description it will be appreciated that the present invention consists-broadly of a fluid pressure-operated striker rod' designed to set off a detonating cap within a blasting. cartridge; -It 7 will be understood, ofcourse, that suitable piping maybe connected withthe cylinder 13 at the inlet opening Hand that the operating fluid pressure maybe" generated and controlled until a predetermined pressure is exerted thereon. 2,

2. A blasting cartrid 'e comprising'a sub.- stantially cylindrical %ody having a chamber formed therein, an end of said cartridg'e having a transversely arran ed pocket therein with a .passage placing sai pocket in. communication with said gas chamber and a secondpassage leading from the exterior or said cartridge into said pocket, anda valvein said pocket for controlling communication between the pocket and the first said passage.

Signed at Chicago, Illinois, this 2nd day. i

of October, 1929. a LAWRENCE E. LAWSON.

from a remote point. Snecifically,-the invention contemplates a fluid. pressure operated striker rod in'combinationwith a-means for Y preventing-accidental displacement thereoj and. also holding the same against movement until a predetermined pressureis exerted thereon in order that the actionof the striker.

rod may be rapid and forceful. invention' therefore provides an .entirely' safe ine'thodef efiecting the discharge of blasting i cartridges without the aid .of electricity or other dangerousIforms of power.

I claim: i

a LfA blasting cartridge comprising a stantially, cylindrical casing having a gas 5: chamber-formed therein a heater support 7 mounted in said casing,-a heater unit positioned within said support with an end there- I of adjacent one end "wall of. the chamber, a striker rod extending through said end wall D in proximity to the end of said heater, a pylinwithin said cylinder and having connection din-associated-with 'said cartridge, a piston.

witha source of fluid pressure, and a frangible pin associated with said striker rod-for {retaining the same in inoperative position v;

its 

